sodra

Hi! I took a 1/4" cable output from a guitar effect pedal, and I soldered wires to them. Now, I'm not sure if I need some transistors to hook it up to the arduino.I need to connect the Arduino to my Guitar Amp with it.

Do I need any transistors so I can hook it up properly?

Also, Is there a way I can read the hertz of a note through the arduino?

Probably worth looking for some free software guitar-tuner and seeing how it does it. It may be quite simple to do if you are prepared to wait a bit, harder to do quickly. FFT is overkill when looking for one frequency, correlations and convolutions are the sort of technique to use and you only need 8-bit samples for this kind of task anyway. For instance correlating with a chirp might yield useful results.

You will need a grounding in signal processing though...

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